What if We Fail?

In the gita, vishnu slash christna is saying, look, i'm the prime mover here. I'm the one who destroys you. Just do your duty. Openheimer seems to be implying that there perhaps is no all powerful force that bears the burden of our deeds. The burden is instead on the shoulders of those involved in the creation of such a weapon. It's this really perplexing and beautiful passage.